Asthma is a leading cause of hospital admission and absenteeism among school children, and this problem is thought to be more severe among inner city children. Many studies have suggested an important role for indoor allergens in asthma and recently it has become possible to measure dust mite, cat and cockroach allergens in house dust. A recent study on children presenting to an inner city hospital with asthma showed that both mite and cockroach sensitization were common among these patients. However, too little is known about the role of indoor allergens in asthma among urban or African American children. The current proposal is to use a validated protocol to screen about 600 children in 7th and 8th grades in Charlottesville City Schools and then to study 60 asthmatics and 60 random controls in detail. From our previous surveys we expect to identify at least 30 children who are on regular treatment for asthma and at least 30 more who have symptoms. The detailed study would involve skin tests; bronchial provocation with histamine; serum assays for IgE and IgE antibodies; as well as house visits to collect dust which will be assayed for mite, cat and cockroach allergens. The question is how common sensitization to the major indoor allergens is among the asthmatics and among the populations from which they come. These results will be compared to those from previous studies on school children in Albemarle County, VA and in Los Alamos, New Mexico. The results will provide an accurate assessment of the prevalence of wheezing and asthma treatment among these children. Further, they will provide more information about the levels of indoor exposure which increase the prevalence of sensitization and asthma. In the second specific aim, houses of children with asthma will be studied in detail to identify both the levels of allergens in the houses and specific problems with controlling exposure. This will include testing the effects of cockroach control measures on live roaches, allergen levels and airborne allergen. Next, specific measures designed to reduce overall allergen exposure (i.e., to mites, cockroach and other allergens) will be tested in these urban houses. The results will provide the background necessary for developing allergen avoidance protocols suitable for the treatment of asthma among inner city children.